FDG-PET/CT in the Assessment of Global Brain Metabolism in Cardiovascular Disease

1578 Objectives: The goal of this study was to assess global cerebral glucose metabolism in subjects with known cardiovascular risk factors and healthy controls by employing a quantitative 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) technique. We hypothesized that subjects at-risk would demonstrate decreased global brain glucose metabolism and therefore brain function compared to healthy controls. Methods: The present study compared 35 healthy male controls and 14 male subjects at increased risk for cardiovascular disease (CVD). All subjects were grouped into two age-matched cohorts: younger (<50 years; age at-risk=34.6±7.4 yr, control=38.7±10.6 yr) and older (≥50 years; at-risk=58.4±6.7 yr, control=60.3±7.1 yr). The average mean standardized uptake value (Avg SUVmean) was measured by mapping regions of interest (ROIs) of the entire brain across the supratentorial structures. Wilcoxon’s rank-sum test was used to assess the differences in Avg SUVmean between controls and at-risk subjects. Results: Younger subjects demonstrated lower global brain Avg SUVmean than older subjects. In the younger cohort, at-risk subjects demonstrated significantly lower global brain Avg SUVmean than healthy controls (at-risk=8.51, control=7.14, p<0.0355). Similarly, in the older cohort, at-risk subjects demonstrated significantly lower Avg SUVmean than controls (at-risk=7.12, control=6.58, p<0.0343). Conclusions: Global brain glucose metabolism appears to be influenced by chronic cardiovascular risk factors. Therefore, FDG-PET/CT may play a role in determining the importance of CVD on brain function and its potential for monitoring the efficacy of various therapeutic interventions.